Electrically actuated or electrically assisted steering systems including rotary-to-linear mechanisms such as ball-screw assemblies provide power assist to a steering assembly, for example, by providing a nut surrounding and threadably engaged with a screw portion of a rack such that rotation of the nut by a motor imparts axially directed force to the rack, thereby assisting the driver in steering the vehicle. In a ball-screw assembly, the threaded engagement of the nut and screw is through a plurality of balls disposed in threads or ball grooves formed in the ball-nut and ball-screw. However, deflection of the nut or screw may cause misalignment that results in high friction between the nut and screw, and excessive wear and tear of the mechanism.
It is desirable to accommodate such misalignment while maintaining performance of the mechanism.